Centerless grinding of elongated rollers that are curved lengthwise



Jan. 3, 1950 A. H. LUNDIUS 2,493,302

CENTERLESS GRINDING OF ELONGATED ROLLERS THAT ARE CURVED LENGTHWISEFiled May 1, 1947 2 Sheets-Sheet l I 1 I 90 i R /2 o I 76 4 1 h .415 V86 F1q24 4m,

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Fi z BY M w Hi5 ATTORNEY Jan. 3, 1950 A. H. LUNDIUS 2,493,302

CENTERLESS GRINDING 0F ELONGATED ROLLERS THAT ARE CURVED LENGTHWISE IFiled May 1, 1947 2 Sheets-Sheet 2 Illlllllllllllllllllll 32. 6/ Fig. 7

0'"? Q E i 1' I Q 4 (,l L 50 O Q Fz' 10 H 8 44 9 O Q /N\i/ENTOR H 15 ATTORNEX Patented Jan. 3, 1950 CENTERLESS GRINDING OF ELONGATED ROLLERSTHAT ARE CURVED LENGTH- WISE Alton H. Lundius, East Orange, N. Jassignor to General Motors Corporation, Detroit, Mich., a

corporation of Delaware Application May 1, 1947, Serial No. 745,333

11 Claims.

This invention relates to the centerless grinding of elongated rollersthat are curved lengthwise and comprises all of the features of noveltyherein disclosed. An object of the invention is to provide improvedmechanism for generating an arcuate longitudinal curvature on elongatedrollers such as barrel shaped rollers for selfaligning bearings. Anotherobject is to provide a centerless grinding machine which will act withgreater speed and less idle time than previous machines for the purpose.To these ends and also to improve generally upon machines of thischaracter, the invention consists in the various matters hereinafterdescribed and claimed. In its broader aspects the invention is notnecessarily limited to the specific construction selected forillustrative purposes in the accompanying drawings in which Fig. 1 is aplan view with parts in horizontal section below the upper work blade.

Fig. 2 is a front elevation.

Fig. 2A is a central sectional view of portions of the wheels and thework blades, the work piece being enlarged.

Fig. 3 is a perspective view of the moving parts of the roller feedingmechanism.

Fig. 4 is a plan view of the upper blade and its holder.

Fig. 5 is a front view of a loading block.

Fig. 6 is a side View of the machine, the wheels and part of the feedingmechanism being removed.

Fig. 7 is a plan view of the base plate.

Fig. 8 is a front view of Fig. '7.

Fig. 9 is a plan view of the lower blade holder.

Fig. 10 is a front view of Fig. 9.

The rollers W, herein shown as of the elongated type curved lengthwisesuch as symmetrical barrel shaped rollers, are ground by a concave ortransversely curved grinding wheel G along which they travel endwise inan arc while rotated and advanced by a regulating wheel R which has aspiral groove 2 and a spiral rib 4 with a plurality of turns. The bottomof the groove is curved to fit the rollers and form a seat therefor.Since the curve of the groove and the curvature of the grinding wheelare directly opposed, the rollers are self-centering and do not dependon the sides of the rib to advance them. The regulating wheel is securedto a flanged hub 6 by a flanged nut 8 and is rotated upwardly at thework by a shaft 10. A cam l2 having arcuate slots [4 is adjustablysecured to the regulating wheel by screws. As will later appear, thiscam controls the feeding of the rollers to the regulating wheel. As therollers travel endwise between the wheels, they are loosely confined forrotation between a curved upper blade 16 (Fig. 6) and a curved lowerblade l8. The lower surface of the upper blade except at one end slantsdownwardly away from the regulating wheel and the upper surface of thelower blade slants downwardly towards the regulating wheel. The bladeshave work guiding surfaces which extend beyond the sides of the wheelsand their length is greater than that of a plurality of rollers.

The upper blade is clamped to a curved blade holder 26 by clampingplates 22 each having a little lip engaging the blade holder next to ashoulder and a slanting edge engaging the end of the blade. The bladeholder has a slotted extension secured by screws 24 in a groove of anupright standard 26 secured by a key or projection 28 and bolts to onevertical edge of a flange or web 30 on base plate 32. In order that therollers may be introduced laterally or sidewise between the blades intothe spiral groove of the regulating wheel from one side of the grindingwheel, the upper blade is cut away at 34 adjacent to one end to form aroller passage and another portion is cut away at 36 to clear thefeeding mechanism. Between the wheels, the adjacent edges of the bladesare closer together than the diameter of the rollers and they presentbevelled roller confining edges towards the regulating wheel. Thegrinding wheel is slabbed off or narrower than the regulating wheel toprovide space for the feeding mechanism and to expose a turn of thespiral groove. The center of transverse curvature of the grinding wheellies in the central plane of the regulating wheel and hence the grindingwheel is unsymmetrical. The blade curvature has the same center ofcurvature and both blades fit up close to the grinding wheel.

The lower blade I8 is supported and adjusted vertically by a stud 38threaded in the base plate, the blade then being secured by clampingplates it to a saddle or blade holder 42. Each clamping plate has alittle lip (Fig. 1) engaging the blade holder next to a shoulder and aslanting edge to engage the end of the arcuate blade. The blade holderis located vertically by two pins it projecting from the flange or web30, the blade holder being secured to the web by screws passing throughcountersunk holes into tapped holes in the web. To clear the grindingwheel, the web 30 is notched at 46 and its rear face is steeply inclinedbelow the notch. The blade holder has a similar clearance notch at 41with the rear face similarly inclined. An opening 48 3 in the webprovides for access to one of two vertical bolts 49 by which the baseplate is adjustably secured to the frame of a centerless grinder (notshown), the bolts passing down through slots in the base plate into theframe.

The rollers W are urged endwise through an inclined feed tube 50 fromwhich they enter a hole in a loading block 52 and pass into a loadinggroove or roller locating recess 54 where the rollers in successionimpinge against a hardened stop plate 56. This locates the endmostroller in alignment with the spiral groove of the regulating wheelbefore being pushed into the groove sidewise through the roller passageat 34 in the upper blade. The loading block has a bottom tongue enteringa groove in a horizontal projection 58 on a vertical standard 60 whichhas a locating tongue or key entering a vertical groove in the web 30,the standard being secured in vertically adjusted position by screws 62.

The rollers are pushed sidewise in succession from the loading groove 5by an oscillating feeding finger 64 whose shank is slotted andadjustably clamped by a screw 86 in a groove of an angular bracket 68.The upper leg of the bracket 68 is slotted and adjustably secured byscrews to a horizontal face on a support 12 which has a flattenedvertical shank l3 pivoted at 74 between flanges on a vertical lever arm16. The support 12 is urged against a'shoulder on the lever arm by acoil spring 86 which surrounds a threaded stud 82 passing through avertical slot in the support '12 and'fixed to the lever arm. The springis interposcd between the support and an adjusting nut and can give toallow the support to swing around its pivot in case the rollers getjammed. f'he lever arm forms part of a bell crank lever which is pivotedat'84 between lugs projecting at an angle from a bracket 86 which hasfour attaching ears secured by screws to the Web 30. The horizontal armof the bell crank lever is bent at the end and carries a cam roll '88running on the above mentioned cam I2 which rotates with the regulatingwheel. The cam roll is held against the cam by a coil spring 90 which isanchored to a bent bracket 92 fastened to the top of the web 39.

At each revolution of the regulating wheel and the cam, the feedingfinger advances and a roller is pushed from the loading groove 54 overthe lower blade into the spiral groove 2 of the regulating wheel. Thepitch of the groove and the rotation of the regulating wheel cause theroller to advance endwise along the blades and between the wheels forcenterless grinding. Since there are several turns to the spiral groove,a plurality of rollers are simultaneously in engagement with the wheelsand there is no idle time.

I claim:

1. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral groove the bottom of which is curved tofit the rollers, a grinding wheel having an arcuate contourtransversely, the center of curvature being substantially in the centralplane of the regulating wheel, one side of the grinding wheel beingslabbed off to make it unsymmetrical and narrower than the regulatingwheel to expose the spiral groove, a curved work blade immovably fixedbetween the wheels and conforming to the curve of the grinding wheel,said blade having a work guiding surface of a length greater than thewidth of the grinding wheel, means for introducing rollers one at a timeinto the groove, and means for rotating the regulating wheel to cause 4the spiral groove to push the rollers endwise along the fixed blade.

2. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral groove the bottom of which is curved tofit the rollers, a grinding wheel having an arouate contourtransversely, the center of curvature being substantially in the centralplane of the regulating wheel, one side of the grinding wheel beingslabbed off to make it unsymmetrical and narrower than the regulatingwheel to expose the spiral groove, a curved work blade fixed between thewheels and having substantially the same center of curvature as thetransverse contour of the grinding wheel, means for rotating theregulating wheel to cause the spiral groove to push the rollers endwisealong the fixed blade, and means controlled by every revolution of there ulating wheel for pushing one rollar laterally into the spiral groovefrom the slabbed off side of the grinding wheel.

3. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral groove the bottom of which is curved tofit the rollers, a grinding wheel having an arcuate contourtransversely, the center of curvature being substantially in the centralplane of the regulating wheel, a curved work blade immovably fixedbetween the wheels and conforming closely at its edge to the curve ofthe grinding wheel, said blade having a work guiding surface extendingfrom one side of the regulating wheel to the other, means for rotatingthe regulating wheel to cause the spiral groove to push the rollersendwise along the fixed blade, and means for introducing rollers one ata time into the groove, the groove having a plurality of turns 50 that aplurality of rollers are simultaneously advanced along the grindingsurface of the fixed blade by the groove.

4. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral groove the bottom'of which is curved tofit the rollers, a grinding wheel having an arcuate contourtransversely, upper-and lower blades between the wheels and each curvedto conform closely to the curve of the grinding wheel, the adjacentedges of the blades being slanted to present bevelled roller engagingedges toward the regulating Wheel and one of said edges having acut-away portion at one end to provide a passage larger than a roller,means for introducing rollers through said passage to the spiral groove,and means for rotating the regulating wheel to cause the spiral grooveto push the rollers endwise along the blades and the grinding wheel.

5. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral groove the bottom of which is curved tofit the rollers, a grinding wheel having an arcuate contourtransversely, one side of the grinding wheel being slabbedoif to make itunsymmetrical and narrowerthan the regulating wheel to expose the spiralgroove, upper and lower curved blades between the wheels, the edges ofthe blades being slanted to present roller confining edges towards theregulating wheel and one of said edges having a cut-away portion at oneend to provide a roller passage, means for rotating the regulatingwheel, and means controlled by every revolution of the wheel for pushingone roller laterally through the passage into the spiral groove fromtheslabbed off side of the grinding wheel.

6. In a machine for grinding rollers that are curved lengthwisaaregulating wheel having a spiral groove with a plurality of turns, agrinding wheel having an arcuate contour transversely, a curved workblade fixed between the wheels and conforming at its upper edge to thecurvature of the grinding wheel, means for rotating the regu latingwheel to cause the spiral groove to push a plurality of rollerssimultaneously along the blade, and means for introducing a roller overthe blade into the groove at every revolution of the regulating wheel.

7. in a machine grinding rollers that are curved lengths 'se, aregulating wheel having a spiral groove w in a plurality of turns, agrind-= ing Wheel h ving arcuate contour transversely, a curved a oladeconformi at its up to the curvature of the grindir wheel, means forrotating the regulating wl i to cause the spiral groove to push aplurality of rollers simultaneously along the blade, a loading blockhaving means to locate the rollers endwise in succession with theirperipheries in alignm it with the groove, and means actuated everyrevolution of the regulating wheel for pushing a roller sidewise intothe spiral groove from the loading block.

8. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral. groove with a plurality of turns, agrinding Wheel having an arcuate contour transversely, a curved workblade fixed between the wheels and conforming at its upper edge to thecurvature of the grinding wheel, means for rotating the regulating wheelto cause the spiral groove to push a plurality of rollers simultaneouslyalong the blade, a loading block having a roller locating grooveadjacent to the spiral groove, a feeding finger movable through theloading groove, and a cam fixed to the regulating wheel for oscillatingthe feeding finger to push a roller sidewise from the loading grooveinto the spiral groove at every revolution of the regulating wheel.

9. In a machine for grinding rollers that are curved lengthwise, aregulating wheel having a spiral groove with a plurality of turns, agrinding wheel having an arcuate contour transversely, a curved workblade fixed between the wheels and conforming at its upper edge to thecurvature of 1 between the wheels and the grinding wheel, means forrotating the regulating wheel to cause the spiral groove to push aplurality of rollers simultaneously along the blade, a loading blockhaving a roller locating recess, a feed tube for conducting rollersendwise into the recess, a feeding finger in alignment with the recess,a bell crank lever supporting the finger, and a cam fixed to theregulating wheel to oscillate the lever and cause the finger to push aroller sidewise into the spiral groove.

10. In a machine for grinding elongated rollers, a regulating Wheelhaving a spiral groove, a grinding wheel one side of which is slabbedoil? to make it narrower than the regulating wheel and expose the spiralgroove, upper and lower blades extending between the wheels and beyondthe grinding wheel, the portions of the blades between the Wheels beingcloser together than the diameter of the rollers and a portion of oneblade beyond the Wheels being cut away to provide a roller passage, andmeans for introducing rollers sidewise one at a time through the passageinto the spiral groove from the slabbed off side of the grinding wheel.

11. In a machine for grinding elongated rollers, a regulating wheelhaving a spiral groove, a grinding wheel one side of which is slabbedofi to make it narrower than the regulating wheel and expose the spiralgroove, a fixed work blade extending between the wheels and beyond theslabbed ofi side of the grinding wheel, a reciprocating feeding fingermovable in the direction of the depth of the groove for pushing a rollerlaterally over the blade into the groove from the slabbed off side ofthe grinding Wheel.

ALTON H. LUNDIUS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Cramer May 2,1939

